DATEC · Inversion of seismic and gravity data to infer the density and thermal structure under the European continent
FP6 — Marie Curie Actions (Human Resources and Mobility)
- Duration
- 2007-03-01 → 2008-02-29
- EU contribution
- €40,000
- Participants
- 1
- Scheme
- EIF
Lines connect the coordinator with its partners.
Results in brief
Final Activity Report Summary - DATEC (Inversion of seismic and gravity data to infer the density and thermal structure under the European continent)
Within the first year of this project, tomographic inversion of P body waves, fundamental mode Love and Rayleigh wave group speed measurements, and gravity data allow us to reconstruct Vp, Vs and upper mantle density structure below the Euro-Mediterranean area, down to 250 depth. PM0.5 P-wave tomography of the Alpine-Mediterranean area (Piromallo and Morelli, 2003) and the new transversely isotropic shear wave velocity model of the upper mantle in the European and Mediterranean region (Schivardi and Morelli, 2007) are inverted with the Bouguer anomalies computed from the satellite GGM02C (Tapley et al., 2005) high resolution global gravity model. The approach uses a probability density function, where the information given by the seismic model and the information on the physical correlation among the density and the velocity parameters limit the model space within that the inversion of gravity data can operate. The density model parametrisation which uses polyhedral bodies whose density is linearly dependent on the three coordinates (Pohànka, 1998) leads to a perfect match between the density and the velocity models and takes into account the presence of structures characterized by a gradual increase in density with depth. Taking in account the data resolution, we define the cell model with a horizontal regular spacing of 1° x 1°. The model horizontal dimensions are approximately of 6600 km in E-W direction, 3900 km in N-S direction. The vertical spacing is 50 km. The parallelisation of the codes allow the inversion of fully populated matrices with 50,000 x 50,000 values. Accurate investigation of the physical relationships between Vp, Vs and bulk densities for the crust and the upper mantle up to 300 km have been conducted considering the information of both seismological and gravity data. This analysis can open new avenues for research in seismology, in those fields where the above physical relationships are needed.
Data: CORDIS, © European Union
Project objective
In the European continent, large scale structural heterogeneities, probably related to its thermal regime, coexist with local specific tectonic structures, some of them like the Alpine-Carpathian-Pannonian system, still to be definitely understood. With this project, we aim to constrain the bulk seismic and density structure of the Earth's upper mantle beneath the European continent through the joint inversion of body and surface seismic waves and satellite gravity measurements.The recovered density model will then be used as a reference in order to infer the upper mantle thermal structure of the studied area. In relationship to state of the art" of research in the field, three goals for this project may be identified: - to exploit the complementary information carried by body waves and surface waves, and gravity measurements, when applied to continental-scale studies of the deep Earth structure, to infer variations of elastic parameters and density (k, mu, rho); - to constrain the mantle geotherm by density anomalies, recovered with the independent contribution of gravity measurements; - to recover the European upper mantle geotherm, constrained by two independent geophysical data-sets.The need of this research is primarily scientific, as the Earth's average profiles of temperature are key parameters to understand mantle dynamics, and a number of still unresolved tectonic and magmatic activities (e.g. generation and upwellings of mantle plumes). As a result, the comprehension of these activities, is also fundamental for the assessment of the seismic and volcanological risk in the continent. The completion of the research project will be relevant for a number of Earth sciences disciplines like Seismology, Geodesy, Petrology, Geochemistry."
Original text from CORDIS.
Participants
- ISTITUTO NAZIONALE DI GEOFISICA E VULCANOLOGIA · ROMACoordinatorItaly
Links
Data: CORDIS, © European Union